The key idea that makes the machine work is that the magazine is just a row of dominoes dragged along the table. This avoids the problem of having to somehow lower the dominoes onto the table. My first unsuccessful attempts back in 1985 involved dropping the dominoes out of the magazine onto the table. But the impact of dropping the dominoes would often cause them to tip over, with ruinous consequences.

Project pics and much more of his process can be located over at WoodGears. [Thanks, Mark!]